Abstract: High-temperature molten salt heat storage is an effective solution for energy issues. Structure and design parameters of a molten salt-water heat exchanger play decisive roles in its performance. Software HTRI was taken in detailed design and selection on the molten salt-water heat exchanger with megawatt capacity. Manufacturing dimensions and rated performance parameters of the molten salt-water heat exchanger were achieved after data correction. Based on its design parameters, the exchanger's dynamic load, molten salt temperature at inlet and outlet, effective average temperature difference, steam temperature at outlet, design margin of heating area and heat transfer coefficient were simulated and calculated by controlling its water flow and molten salt flow. The calculation results show that the designed molten salt-water heat exchanger can complete 1 MW heat exchange，and its dynamic heat exchange performance is in line with the manufacturing dimensions of tube and shell heat exchangers. The reasonable design for the molten salt heat exchanger provides reliable reference for further research.

Key words: heat storage, molten salt, heat supply, heat exchanger, design and selection, dynamic performance